It is known in regard to the raising of animals, particularly cows and dogs, that a device may be provided to detect the onset of the birthing process commonly by attaching the device to the vagina or vulva of the animal so that a signal can be generated and communicated to the operator. Examples are shown in European Application 108,330 (Weiland) published 16 May 1984, in U.S. Pat. No. 4,264,900 (Charlier) issued 28 Apr. 1981 and in U.S. Pat. No. 4,319,583 (Ingle) issued 16 Mar. 1982.
Also in U.S. Pat. No. 4,651,677 (de Wit) issued Mar. 24, 1987 is shown an arrangement in which a microphone detects sounds emitted by a sow and/or the piglets and analyzes the sounds to determine the condition of birthing or crushing of the piglets to summon the operator. This arrangement is apparently not currently available in the market place.
The problem of monitoring the onset of birth can of course be resolved by providing enough work people to ensure that sows are closely visually monitored to ensure that the person is available as soon as possible after the onset so that all viable piglets are extracted and protected. However many such hog facilities are located in areas where labor costs are such that close monitoring of this nature is not economically feasible.
However despite the proposal of the above techniques for detecting the onset of birth of the piglets, in practice this remains a problem and no effective economic systems are available for this purpose.
Another aspect of protecting piglets after birth is that of providing a suitable location within the farrowing pen for receiving and containing the piglets while keeping them away from the sow where they can be crushed.
In U.S. Pat. No. 4,478,175 (Fisher) issued Oct. 3, 1984 is disclosed a temperature controlled heated nest box for the piglets after birth.
In a brochure by Veng Systems is disclosed a heating lamp and cover panel arranged to be located in the farrowing pen with a temperature sensor to maintain the covered area of the pen at a predetermined temperature for the piglets. No patent or published patent application describing this machine has been found.
Other patents and published documents in this general field are as follows:
PCT/DK2001/000812, WO 02/046850, Inventor: Niels Skov Veng which discloses a control system.
French Patent: FR2579452A1, Inventor: Guy Houssin, registered 29 Mar. 1985 which discloses a device including a contact which is displaced by an arriving piglet for detecting birth;
French Patent: FR2582507A1, Inventor: Paul Fuseau, registered 4 Jun. 1985 which discloses a device mounted in the uterus for detecting the onset of birth;
PCT Published Patent Application WO03/056907A1, Inventor: Jan Tambo, published the 17 Jul. 2003 which discloses a heating control system for piglets.
US Published Patent Application 2007/0262859 Inventor: Marjolaine Henry, published the 15 Nov. 2007 which discloses detection of the birthing process either by a motion sensor or by a weight sensor at the piglet area and the transmission of a signal to the worker in the barn.